How a Tin Ingot Quotation Is Actually Built
Refined tin ingot is a commodity metal, so no smelter sets a price from a catalogue. A delivered number is assembled from four layers: the exchange benchmark for standard refined tin, the producer ex-works conversion cost, the physical premium attached to the exact grade and shape, and the logistics and duty layer that moves the metal from smelter to buyer gate. Teams that quote only the benchmark and add a flat margin typically land 3-8% away from the real cost, because they ignore packing weight, remelt loss and financing on the pricing window.
The Four Pricing References Buyers Should Track
1. Exchange benchmark. Exchange-traded refined tin contracts in London and Shanghai are the anchor of the market. The benchmark is a cash or near-dated settlement for standard-grade refined tin, published in USD per tonne or CNY per tonne. Most Asian contracts are indexed to the arithmetic average of a defined quotation window (a month or a half month) instead of a single pricing day, which removes the risk of an abnormal spike on the settlement date.
2. Producer ex-works cost. This is the smelter's own number and contains feed cost (concentrate or secondary tin-bearing scrap), energy, refining charge, labour, tax and smelter margin. In practice it is quoted as a premium or a discount to the benchmark, never as a standalone absolute figure.
3. Physical premium. Grade, shape, packing and mill approval create a genuine premium. A 99.99% ingot cast in 25 kg bars and palletised is not priced like a 99.90% ingot shipped loose in bundles.
4. Futures and trade layer. Where a contract carries a pricing period, the buyer may hedge on futures; the hedge cost or gain becomes part of the landed number.
Converting a Benchmark into a Landed Price
The weighted-average calculation that most purchasing departments use:
Landed cost = B x (1 + P) + C + F + D + T
| Symbol | Cost element | Typical basis |
|---|---|---|
| B | Benchmark average | Monthly or half-month mean of the published refined tin settlement |
| P | Physical premium | 0.5-3% for standard 99.9% ingot, higher for 99.99% and special packing |
| C | Conversion / remelt charge | Per tonne, quoted by the producer |
| F | Freight and insurance | Per tonne, port to port |
| D | Duty and clearance | Percentage of the customs value |
| T | Sampling, assay, weighing | Per lot |
Worked example. With a benchmark average of 26,000 USD/t and a 1.5% premium, the metal layer is 26,390 USD/t. Add a 500 USD/t conversion charge, 180 USD/t freight, 2% duty and 60 USD/t of assay and weighing, and the delivered figure is close to 27,620 USD/t before financing. Notice that duty multiplies the metal and freight layer, not the conversion charge - a detail that is frequently mis-keyed in buyer spreadsheets.
Grade, Purity and Standard Requirements
| Designation | Tin content, min. | Typical end use |
|---|---|---|
| Sn99.90 | 99.90% | General solder alloys, tinning baths, bronze |
| Sn99.95 | 99.95% | Solder, coating, chemical conversion |
| Sn99.99 | 99.99% | Electronics, high-purity chemicals, sputtering targets |
Refined tin is covered by national and international specifications, including GB/T 728 for tin ingot in the Chinese market and ASTM B339 / B339M for pig tin. Standard ingots are conventionally cast at approximately 25 kg with dimensions agreed between producer and buyer, and each lot is accompanied by a certificate of analysis. The constants used for weight, volume and melting calculations are density 7.28 g/cm3 and melting point 231.9 degC. Impurity limits for Fe, As, Cu, Pb, Bi, Sb and S tighten as the grade rises, so the grade choice should follow the alloy being made, not the warehouse stock position.
Cost Lines That Are Left Out of Tin Budgets
Four items quietly move a tin ingot budget. First, packing weight: a palletised lot carries roughly 1-2% of additional mass in pallets, strapping and liners. Second, remelt loss: where the buyer re-melts ingots, expect 0.3-1.0% metal loss to dross depending on furnace type and cover flux. Third, financing: a 30-day pricing window at 6% annualised costs about 0.5% of metal value. Fourth, packaging replacement and fumigation for sea freight, which can add 20-60 USD per tonne to the landed number. A price model that omits these four lines will understate the cost of every tonne purchased.
Frequently Asked Questions
Q: Is the tin ingot price simply the exchange price?
A: No. The exchange settlement is only the metal layer. The delivered price also includes the producer conversion charge, the physical premium for grade and packing, freight, insurance, duty and assay cost.
Q: Which grades of tin ingot are normally traded?
A: The three commercial grades are Sn99.90, Sn99.95 and Sn99.99. Higher purity is used for electronics and high-purity chemicals, while 99.90% is sufficient for many solder and tinning applications.
Q: Why is a monthly average used instead of a single day?
A: Averaging over a defined window smooths out short-term volatility and prevents an abnormal single-day settlement from distorting the contract value for either side.
Q: How much remelt loss should be budgeted?
A: Typically 0.3-1.0% of the charged weight when ingots are re-melted in an open or induction furnace. The exact figure depends on furnace atmosphere, cover flux and holding time.
Q: Does ingot shape change the price?
A: Yes. Standard 25 kg cast bars are the lowest-cost form. Smaller bars, custom dimensions, strapping and palletising add handling and packing cost, and are normally reflected as a premium over the standard shape.
Q: What should be checked on the shipping documents?
A: Net and gross weight, tin content on the certificate of analysis, lot or heat number, packing count and port of loading. Weighing discrepancies above 0.2% should be raised before the pricing window closes.